//===== Copyright (c) Valve Corporation, All rights reserved. ======//
//
// Purpose: 
//
// $NoKeywords: $
//==================================================================//

#ifndef VTF_DECLARATIONS_H
#define VTF_DECLARATIONS_H

#ifdef _WIN32
#pragma once
#endif

//-----------------------------------------------------------------------------
// Forward declarations
//-----------------------------------------------------------------------------
class CUtlBuffer;
class Vector;
struct Rect_t;
class IFileSystem;

//-----------------------------------------------------------------------------
// Texture flags
//-----------------------------------------------------------------------------
enum CompiledVtfFlags
{
	// Flags from the *.txt config file
	TEXTUREFLAGS_POINTSAMPLE	               = 0x00000001,
	TEXTUREFLAGS_TRILINEAR		               = 0x00000002,
	TEXTUREFLAGS_CLAMPS			               = 0x00000004,
	TEXTUREFLAGS_CLAMPT			               = 0x00000008,
	TEXTUREFLAGS_ANISOTROPIC	               = 0x00000010,
	TEXTUREFLAGS_HINT_DXT5		               = 0x00000020,
	TEXTUREFLAGS_PWL_CORRECTED				   = 0x00000040,
	TEXTUREFLAGS_NORMAL			               = 0x00000080,
	TEXTUREFLAGS_NOMIP			               = 0x00000100,
	TEXTUREFLAGS_NOLOD			               = 0x00000200,
	TEXTUREFLAGS_ALL_MIPS			           = 0x00000400,
	TEXTUREFLAGS_PROCEDURAL		               = 0x00000800,

	// These are automatically generated by vtex from the texture data.
	TEXTUREFLAGS_ONEBITALPHA	               = 0x00001000,
	TEXTUREFLAGS_EIGHTBITALPHA	               = 0x00002000,

	// Newer flags from the *.txt config file
	TEXTUREFLAGS_ENVMAP			               = 0x00004000,
	TEXTUREFLAGS_RENDERTARGET	               = 0x00008000,
	TEXTUREFLAGS_DEPTHRENDERTARGET	           = 0x00010000,
	TEXTUREFLAGS_NODEBUGOVERRIDE               = 0x00020000,
	TEXTUREFLAGS_SINGLECOPY		               = 0x00040000,
	
	TEXTUREFLAGS_SRGB				           = 0x00080000, //SRGB correction has already been applied to this texture.

	TEXTUREFLAGS_DEFAULT_POOL				   = 0x00100000, // Nvidia Stereo Change: Water (Force a texture to the default pool)

	TEXTUREFLAGS_COMBINED					   = 0x00200000,

	TEXTUREFLAGS_ASYNC_DOWNLOAD		           = 0x00400000,

	TEXTUREFLAGS_NODEPTHBUFFER                 = 0x00800000,

	TEXTUREFLAGS_SKIP_INITIAL_DOWNLOAD         = 0x01000000, // Skip initial download when creating a procedural texture

	TEXTUREFLAGS_CLAMPU                        = 0x02000000,
	TEXTUREFLAGS_VERTEXTEXTURE                 = 0x04000000,	// Usable as a vertex texture
	TEXTUREFLAGS_SSBUMP                        = 0x08000000,			

	TEXTUREFLAGS_MOST_MIPS					   = 0x10000000, // Don't load the bottom few mips at runtime

	TEXTUREFLAGS_BORDER						   = 0x20000000,	// Clamp to border color on all texture coordinates

#if defined( _PS3 ) || defined SPU
	// PS3 extensions
	TEXTUREFLAGS_QUINCUNX                      = 0x40000000,
	TEXTUREFLAGS_QUINCUNX_ALT                  = 0x80000000,					
#elif defined( _X360 )
	TEXTUREFLAGS_ALIAS_COLOR_AND_DEPTH_SURFACES = 0x40000000,
	TEXTUREFLAGS_UNUSED_80000000		   = 0x80000000,
#else
	TEXTUREFLAGS_UNUSED_40000000		   = 0x40000000,
	TEXTUREFLAGS_UNUSED_80000000		   = 0x80000000,
#endif
};

enum VersionedVtfFlags
{
	VERSIONED_VTF_FLAGS_MASK_7_3			=	~0xD1780400,	// For a ver 7.3 or earlier only these flags are valid
};


struct VtfProcessingOptions
{
	uint32 cbSize;					// Set to sizeof( VtfProcessingOptions )

	//
	// Flags0
	//
	enum Flags0
	{
		// Have a channel decaying to a given decay goal for the given last number of mips
		OPT_DECAY_R				= 0x00000001,	// Red decays
		OPT_DECAY_G				= 0x00000002,	// Green decays
		OPT_DECAY_B				= 0x00000004,	// Blue decays
		OPT_DECAY_A				= 0x00000008,	// Alpha decays
		
		OPT_DECAY_EXP_R			= 0x00000010,	// Channel R decays exponentially (otherwise linearly)
		OPT_DECAY_EXP_G			= 0x00000020,	// Channel G decays exponentially (otherwise linearly)
		OPT_DECAY_EXP_B			= 0x00000040,	// Channel B decays exponentially (otherwise linearly)
		OPT_DECAY_EXP_A			= 0x00000080,	// Channel A decays exponentially (otherwise linearly)

		OPT_NOCOMPRESS			= 0x00000100,	// Use uncompressed image format
		OPT_NORMAL_DUDV			= 0x00000200,	// dU dV normal map
		OPT_FILTER_NICE			= 0x00000400,	// Use nice filtering
		OPT_SRGB_PC_TO_360		= 0x00000800,	// Perform srgb correction for colormaps

		OPT_SET_ALPHA_ONEOVERMIP		= 0x00001000,	// Alpha  = 1/miplevel
		OPT_PREMULT_COLOR_ONEOVERMIP	= 0x00002000,	// Color *= 1/miplevel
		OPT_MIP_ALPHATEST		= 0x00004000,			// Alpha-tested mip generation
		OPT_NORMAL_GA			= 0x00008000,			// Use Green-Alpha normal compression
		OPT_PREMULT_ALPHA_MIPFRACTION	= 0x00010000,	// Alpha *= miplevel/mipcount 
		OPT_COMPUTE_GRADIENT	= 0x00020000			// Compute normalized du du gradients of green channel and store in r and b
	};

	uint32 flags0;					// A combination of "Flags0"

	//
	// Decay settings
	//
	uint8 clrDecayGoal[4];			// Goal colors for R G B A
	uint8 numNotDecayMips[4];		// Number of first mips unaffected by decay (0 means all below mip0)
	float fDecayExponentBase[4];	// For exponential decay the base number (e.g. 0.75)

	//
	// Alpha fading with mip levels
	//
	uint8 fullAlphaAtMipLevel;
	uint8 minAlpha;
};


//-----------------------------------------------------------------------------
// Cubemap face indices
//-----------------------------------------------------------------------------
enum CubeMapFaceIndex_t
{
	CUBEMAP_FACE_RIGHT = 0,
	CUBEMAP_FACE_LEFT,
	CUBEMAP_FACE_BACK,	// NOTE: This face is in the +y direction?!?!?
	CUBEMAP_FACE_FRONT,	// NOTE: This face is in the -y direction!?!?
	CUBEMAP_FACE_UP,
	CUBEMAP_FACE_DOWN,

	CUBEMAP_FACE_COUNT,

	// This is the fallback for low-end (obsolete, here for backward compat!)
	CUBEMAP_FACE_SPHEREMAP = CUBEMAP_FACE_COUNT,

};


//-----------------------------------------------------------------------------
// Enumeration used for spheremap generation
//-----------------------------------------------------------------------------
enum LookDir_t
{
	LOOK_DOWN_X = 0,
	LOOK_DOWN_NEGX,
	LOOK_DOWN_Y,
	LOOK_DOWN_NEGY,
	LOOK_DOWN_Z,
	LOOK_DOWN_NEGZ,
};

#endif // VTF_H